openlibrary_get_cover_url
shallowio.github.cyanheads/openlibrary-mcp-server · Verify this server
Resolve a cover image URL for a book or author photo. Returns a direct HTTPS URL in the requested size (S/M/L). The Covers API always returns HTTP 200 — missing covers return a 1×1 placeholder GIF, not a 404 — so the identifier format is validated locally first: "id" must be numeric, "isbn" 10 or 13 digits, "olid" an edition OLID (OL…M) for target "book" and an author OLID (OL…A) for target "author". Identifiers with path separators or control characters, and author-by-ISBN lookups, are rejected before any request. URLs can be embedded in markdown as .
1 trials · measured 8 days ago
openlibrary_get_cover_url scores 100.0/100 on Vouch's measured behaviour index, from 1 real invocation trials against io.github.cyanheads/openlibrary-mcp-server, measured 25 Aug 2026 under methodology v0.2.0. Every measured component scored 100.
Component breakdown
| Component | Weight | Value |
|---|---|---|
| Reliability | 35% | not applicable |
| Schema integrity | 25% | 100.0 |
| Failure behaviour | 15% | not applicable |
| Latency | 15% | not applicable |
| Concurrency | 10% | not applicable |
Tool details
- Transport
- remote + stdio
- Credential class
- self-provisionable
- Input schema
- not declared
- Output schema
- not declared
- Side-effect classification
- unclassified
Score history
| Day | Score | Tier | Methodology |
|---|---|---|---|
| 2026-08-25 | 100.0 | shallow | v0.2.0 |
Probe evidence
| Probe | Outcomes |
|---|---|
| schema_integrity | pass: 1 |
Raw request/response logs are not archived yet — the outcome counts above are drawn directly from every recorded trial.
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